The present invention relates to a digital broadcasting receiver that uses broadcast channel map information containing channel numbers and virtual channel numbers.
Conventionally, there have been televisions equipped with broadcast channel memories, memories for identifying broadcast stations, etc., which read broadcasting station identification codes for the channels being received, and automatically rewrite desired channels to be received to new broadcast channels by going through search processes when the broadcast channels are changed (e.g., Japanese Unexamined Patent Publication No.11-18018).
Furthermore, in recent years, broadcasting stations in North America have been distributing digital broadcasts based on the ATSC (Advanced Television Systems Committee) Standards. As a result, certain types of broadcasting receivers (set top box; hereinafter called “STB”) are becoming popular that receive these digital broadcasts and convert them into image signals that can be received by existing televisions. The STB typically is equipped with table data (“channel map”), which stores in an internal memory the data included in the broadcasting signal at the time when the broadcasting signal is received, and this channel map is used for the purpose of station selection later. It is possible to provide the STB with a capability of automatically rewriting the desired channel to be received to a new broadcast channel by going through the abovementioned search process.
However, the STB of the prior art could not select a station if the digital channel number inputted by a user was not registered in the channel map, so that it used to notify the user that there was no signal even though the broadcasting signal actually existed. More specifically, it was designed in such a way that a digital broadcasting signal could contain information data such as multiple channels (sub-channels) and virtual channel numbers in the same frequency band (“physical channel”), but it was not possible to select stations if the user knew only virtual channel numbers.